Intriguing Tessellations - Marjorie Rice
Famous for discovering four hitherto unknown tilings of pentagons, Marjorie Rice got her start in tessellations reading an article by Martin Gardner. This site features mathematical explanations and examples of several tessellations using pentagons, as
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An Introduction to Fractals - Paul Bourke
"What is a fractal? B. Mandelbrot: A rough or fragmented geometric shape that can be subdivided in parts, each of which is (at least approximately) a reduced-size copy of the whole. Mathematical: A set of points whose fractal dimension exceeds its topological
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Investigating Polygons - Margo Lynn Mankus
The lesson plan for What is the Sum of My Angles? has the objectives of investigating the sum of the measure of the interior angles of a triangle using several methods, and making a mathematical conjecture from observations. The lesson plan for Regular
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Investing in your Future - ThinkQuest 1996
A searchable site for learning the basics of investing. Four financial calculators are available so investors can see how much different investments will return. Follow additional links to the nation's great financial institutions and other exciting places.
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Invest Smart - David Leung, George Lee, and Andy Kim
Learn about the stock market and investment techniques. A Market Simulation lets classes, clubs, or individuals invest an imaginary $100,000 and track the results; includes a separate mutual funds simulation. Site also contains information about saving
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IQFlash.com - Sergey Melnikov
Logic and math games include a variation of Nim, Rhumb Line (similar to tic-tac-toe), and Breakfast Brainstorm (rotate the pans in order to make each of the four numbers equal 20 as soon as possible). Strategy articles include games such as tic-tac-toe,
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Irish Central Statistics Office (CSO)
Statistical information for the country of Ireland from the government body responsible for compiling Irish official statistics. Tables of important socioeconomic data, press releases and publications (available for download in PDF format), and ordering
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Irrational Numbers - Jim Loy
Pythagoras is said to have discovered irrational numbers, showing that the square root of 2 could not be expressed as any whole fraction m/n. Here's the proof...
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Isn't It a Great Time to Be Alive? - Rex Boggs
PDFs and Promethean ActivInspire flipchart files which survey the range of digital technology available to assist in the learning and teaching of mathematics. These free downloads accompanied the talk given by the veteran middle school math teacher to
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I Used To Believe - Mat Connolley
A collection of childhood beliefs, such as thinking that cats are female dogs, that seeds swallowed will sprout fruit from your ears, and a primal fear of toilets. "Some of the beliefs come from overactive imaginations, but a lot are the result of parental
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IXL Learning
IXL provides free online practice, organized by grade levels K-8 and aligned to state standards. Choose one math skill from among the hundreds offered, and submit your answer. Respond incorrectly, and click on the "explanation" button to learn more; get
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Jacopo Notarstefano
Interactive visualizations and puzzles: "Turing's sunflower," which connects leaf arrangements and Fibonacci numbers; "Havel-Hakimi," which presents nodes and their degrees to construct into a graph; "Four-coloring a Dodecahedron"; and a logic puzzle
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Jaina mathematics - MacTutor Math History Archives
Linked essay on the period after the founding of Jainism up to around the time of Aryabhata in around 500 A.D., until recently thought to be a time of little mathematical activity in India. (Jainism is a religion and philosophy which was founded in India
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Jamit Fractions - JAMIT Software
Software for learning fractions, for students from 8 years old to adults. Topics are presented in short lessons, each with references, examples, and a practice game that generates problems to be solved. A free version is on the Web; Part One may be purchased
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